Editing Interstate 66 (section)

== Route description ==
{{lengths table}}
|-
|[[Virginia|VA]]
|74.8
|120.54
|-
|[[Washington, D.C.|DC]]
|1.6
|2.57
|-
|Total
|76.4
|123.11
|}

=== Virginia ===
==== Interstate 81 to Dunn Loring ====
[[File:2018-10-12 11 58 26 View west along Interstate 66 at Exit 1 (Interstate 81, Roanoke, Winchester) in northwestern Warren County, Virginia.jpg|thumb|Western terminus of I-66 at the interchange with [[Interstate 81 in Virginia|I-81]] in [[Middletown, Virginia]]]]
[[File:2018-10-23 12 24 56 View west along Interstate 66 and the Orange Line of the Washington Metro from the overpass for Virginia State Route 243 (Nutley Street) in Oakton, Fairfax County, Virginia.jpg|thumb|I-66 in [[Oakton, Virginia|Oakton]], with a [[Washington Metro]] train using the tracks in the median]]
I-66 begins at a [[directional T interchange]] with [[Interstate 81 in Virginia|I-81]] near [[Middletown, Virginia]]. It heads east as a four-lane freeway and meets [[U.S. Route 522|US&nbsp;522]]/[[U.S. Route 340|US&nbsp;340]] at a [[partial cloverleaf interchange]]. The two routes head south to [[Front Royal, Virginia|Front Royal]] and north to [[Lake Frederick, Virginia|Lake Frederick]]. I-66 continues east and crosses the [[Blue Ridge Mountains|Blue Ridge]] at [[Manassas Gap]], paralleling [[Virginia State Route 55|SR&nbsp;55]] (John Marshall Highway) and meeting [[U.S. Route 17 in Virginia|US&nbsp;17]] at a partial interchange with no access from southbound US&nbsp;17 to westbound I-66. SR&nbsp;55 also merges onto the freeway at this interchange, forming a three-way [[Concurrency (road)|concurrency]] that ends near [[Marshall, Virginia|Marshall]], with SR&nbsp;55 leaving along with [[U.S. Route 17 Business (Marshall, Virginia)|U.S. Route&nbsp;17 Business]] (US&nbsp;17 Bus.) and US&nbsp;17 leaving at the next exit. The freeway then passes through [[Bull Run Mountains|Bull Run Mountain]] at [[Thoroughfare Gap (Bull Run Mountain)|Thoroughfare Gap]].

Expanding to six lanes, and continuing to parallel SR&nbsp;55, I-66 enters the towns of [[Haymarket, Virginia|Haymarket]] and [[Gainesville, Virginia|Gainesville]], reaching interchanges with [[U.S. Route 15 in Virginia|US&nbsp;15]] (James Madison Highway) and [[U.S. Route 29 in Virginia|US&nbsp;29]] (Lee Highway) in each town, respectively. The highway then expands to ten lanes and heads to the south of [[Manassas National Battlefield Park]] and to the north of [[Bull Run Regional Park]]. The highway reaches another interchange with US&nbsp;29 and passes to the north of [[Centreville, Virginia|Centreville]] and meets [[Virginia State Route 28|SR&nbsp;28]] (Sully Road) at an interchange with cloverleaf and stack elements to it. SR&nbsp;28 heads north to [[Dulles International Airport]] and south to [[Manassas, Virginia|Manassas]].

The freeway then meets [[Virginia State Route 286|SR&nbsp;286]] ([[Fairfax County Parkway]]), [[U.S. Route 50 in Virginia|US&nbsp;50]] (Lee Jackson Memorial Highway), and [[Virginia State Route 123|SR&nbsp;123]] ([[Chain Bridge (Potomac River)|Chain Bridge]] Road) at a series of interchanges providing access to D.C. suburbs. The [[Orange Line (Washington Metro)|Orange Line]] and [[Silver Line (Washington Metro)|Silver Line]] of the [[Washington Metro]] begin to operate in the median here, as the highway reaches a large interchange with the [[Interstate 495 (Washington, D.C.)|I-495]] ([[Capital Beltway]]).

I-66 has two tolled [[High-occupancy toll lane|HOT lanes]] from US&nbsp;29 in Gainesville to the Capital Beltway.<ref>{{Cite web |last=Leayman |first=Emily |date=2022-11-29 |title=I-66 Express Lanes Open Ahead Of Schedule In Northern Virginia |url=https://patch.com/virginia/vienna/i-66-express-lanes-open-ahead-schedule-northern-virginia |access-date=2024-04-01 |website=Patch |language=en}}</ref>

==== Dunn Loring to Theodore Roosevelt Bridge ====
The section of I-66 in Virginia east of the Capital Beltway is named the '''Custis Memorial Parkway''',<ref>{{cite web |date=July 14, 2009 |title=Arlington Virginia List of State Roads |url=http://www.arlingtonva.us/Departments/EnvironmentalServices/cpe/row/EnvironmentalServicesState.aspx |url-status=dead |archive-url=https://web.archive.org/web/20060304024247/http://www.arlingtonva.us/Departments/EnvironmentalServices/cpe/row/EnvironmentalServicesState.aspx |archive-date=March 4, 2006 |access-date=2010-08-23 |work=Department of Environmental Services |publisher=[[Arlington County, Virginia#Local government|Government of Arlington County, Virginia]] |quote=I-66 Custis Memorial Parkway}}</ref><ref>{{cite web |title=State Roads |url=https://transportation.arlingtonva.us/streets/state-roads/ |url-status=dead |archive-url=https://web.archive.org/web/20140412013229/https://transportation.arlingtonva.us/streets/state-roads/ |archive-date=April 12, 2014 |access-date=December 27, 2020 |work=Transportation |publisher=[[Arlington County, Virginia#Local government|Government of Arlington County, Virginia]] |quote=Interstate 66: Custis Memorial Parkway}}</ref><ref>{{cite web |title=I-66 |url=http://www.vahighways.com/route-log/i066.htm |url-status=live |archive-url=https://web.archive.org/web/20150613235648/http://www.vahighways.com/route-log/i066.htm |archive-date=June 13, 2015 |access-date=December 27, 2020 |work=vahighways.com: The Virginia Highways Project |quote='''Legislative names:''' Custis Memorial Parkway, I-495 to DC (since 1-21-82)}}</ref><ref>{{cite news|last=Levey|first=Bob|date=November 5, 1981|title=An Honor That Nellie Custis Doesn't Deserve|url=https://www.washingtonpost.com/archive/local/1981/11/05/an-honor-that-nellie-custis-doesnt-deserve/18ed80c2-ee1a-4f68-a5e5-4cae70a71485/|access-date=December 27, 2020|newspaper=[[The Washington Post]]|quote="Ain't no sense in trying to turn it around," said D. D. Harris, an engineer for the Virginia Highway Department. "Arlington County and Fairfax County agreed a year ago to call it the Custis Memorial Parkway. We've even ordered the signs for the entrances.<br />"The only thing that hasn't been done is for final approval to be granted. But that's just dotting I's and crossing T's. It's settled. This is no time to be drumming up business."}}</ref> a [[toll road]] with variable tolls during peak hours.<ref>{{Cite web|title=66 Express Lanes - Inside the Beltway :: About the Lanes|url=http://66expresslanes.org/about_the_lanes/default.asp|access-date=2021-01-09|website=66expresslanes.org}}</ref> The road narrows to four lanes as it heads through [[Arlington County, Virginia|Arlington County]]. The parkway meets [[Virginia State Route 7|SR&nbsp;7]] (Leesburg Pike) at a full interchange. [[Virginia State Route 267|SR&nbsp;267]] (Dulles Toll Road) meets the parkway with an eastbound entrance and westbound exit. Continuing through neighborhoods, the route yet again meets US&nbsp;29 at an incomplete interchange and continues east into Arlington County, meeting [[Virginia State Route 120|SR&nbsp;120]] (Glebe Road) and continuing to Arlington County. It meets [[Spout Run Parkway]] and enters [[Rosslyn, Virginia|Rosslyn]]. The freeway turns southeast and runs in between US&nbsp;29 as it approaches the [[Theodore Roosevelt Bridge]], reaching another eastbound entrance and westbound exit as US&nbsp;29 continues north on the [[Key Bridge (Washington, D.C.)|Key Bridge]]. It then has a complex interchange with [[George Washington Memorial Parkway|George Washington Parkway]] and [[Virginia State Route 110|SR&nbsp;110]] (Richmond Highway), providing access to [[Alexandria, Virginia|Alexandria]] and [[the Pentagon]], respectively. US&nbsp;50 ([[Arlington Boulevard]]) merges onto the highway with a westbound exit and eastbound entrance and the two traverse the bridge.

The "Custis Memorial Parkway" name commemorates the Custis family, several of whose members (including [[Martha Dandridge Custis Washington]], [[George Washington Parke Custis]], [[Eleanor "Nelly" Parke Custis Lewis]] and [[Mary Anna Randolph Custis Lee]]) played prominent roles in [[Northern Virginia]]'s history. Because of its terminus in the [[Shenandoah Valley]], some early planning documents refer to I-66 as the "Shenandoah Freeway", although the name did not enter common use.<ref>{{cite web|title=Department of Planning & Zoning – Planning Zoning|url=http://www.fairfaxcounty.gov/dpz/comprehensiveplan/planhistoric/1984_documents/1984_transportation.pdf|url-status=live|archive-url=https://web.archive.org/web/20170208064206/http://www.fairfaxcounty.gov/dpz/comprehensiveplan/planhistoric/1984_documents/1984_transportation.pdf|archive-date=February 8, 2017|access-date=May 3, 2018|website=www.fairfaxcounty.gov|df=mdy-all}}</ref>

Between the Capital Beltway and the Theodore Roosevelt Bridge, the eastbound (inbound) roadway is a [[high-occupancy toll]] (HOT) road from 5:30 to 9:30&nbsp;am, and the westbound (outbound) roadway is an HOT road from 3:00 to 7:00&nbsp;pm. (Westbound tolling begins after exit 73 to US 29, in order to allow traffic crossing the bridge an opportunity to transfer to free roads.) [[E-ZPass]] is required for all vehicles except motorcycles, including Dulles Airport users. I-66 is free during those times for HOV-3+ drivers with an E-ZPass Flex and for motorcycles. Other drivers must pay a variable toll depending on current traffic levels. Outside of these hours, I-66 is free for all drivers to use.<ref name="express-lanes">{{Cite web|title=66 Express Lanes - Inside the Beltway :: Using the Lanes|url=http://66expresslanes.org/using_the_lanes/default.asp|access-date=2019-09-02|website=66expresslanes.org}}</ref>

=== Washington, D.C. ===
In [[Washington, D.C.]], the route quickly turns north, separating from US&nbsp;50. The highway interchanges with the E Street Expressway spur before passing beneath [[Virginia Avenue|Virginia]] and [[New Hampshire Avenue|New Hampshire Avenues]] in a short tunnel, also running on the east side of the [[Watergate complex]]. After an indirect interchange with the [[Rock Creek and Potomac Parkway]] (via 27th Street), the highway terminates at a pair of ramps leading to the Whitehurst Freeway (US&nbsp;29) and L Street. The portion of Interstate 66 within Washington, DC, is known as the Potomac River Freeway.

==== E Street Expressway ====
{{Infobox road small
|state=DC
|name=E Street Expressway
|location=[[Washington, D.C.]]
|length_mi=0.3
|length_ref=<ref name=estreet-googlemaps>{{google maps |url=https://www.google.com/maps/dir/38.8958094,-77.0512044/38.8954356,-77.0449238/@38.8958443,-77.0491556,18z/am=t/data=!3m1!4b1!4m2!4m1!3e0 |title=E Street Expressway |access-date=January 31, 2020}}</ref>
|formed=
|deleted=
|historic=
|yr_ref=
}}
[[File:2019-09-16 14 49 20 View east along the E Street Expressway from the overpass for 23rd Street Northwest in Washington, D.C..jpg|thumb|The E Street Expressway just east of I-66]]
The '''E Street Expressway''' is a 480 meter long spur of I-66 that begins at an interchange with the Interstate just north of the Roosevelt Bridge. It proceeds east, has an interchange with Virginia Avenue Northwest, and terminates at 20th Street Northwest. From there, traffic continues along E Street Northwest to 17th Street Northwest near the [[White House]], the [[Old Executive Office Building]], [[George Washington University]], and the [[Corcoran Gallery of Art]]. Westbound traffic from 17th Street takes a one-block segment of [[New York Avenue (Washington, D.C.)|New York Avenue]] to the expressway entrance at 20th and E streets northwest. The expressway and the connecting portions of E Street and New York Avenue are part of the [[National Highway System (United States)|National Highway System]].

In 1963, the construction of the E Street Expressway caused the demolition of multiple buildings of the [[Old Naval Observatory]].<ref name=":0">{{Cite web|last1=Harden|first1=Victoria A.|last2=Lyons|first2=Michele|date=2018-02-27|title=NIH's Early Homes|url=https://irp.nih.gov/catalyst/v26i2/nih-s-early-homes|access-date=2020-09-28|website=The NIH Catalyst|language=en}}</ref>

;Exit list
The entire route is in the [[Foggy Bottom]] neighborhood of [[Washington, D.C.]] All exits are unnumbered.{{jcttop|nocty=yes|location=none|hatnote=off|length_ref=<ref name=estreet-googlemaps/>}}
{{DCint
|mile=0.00
|road={{jct|state=DC|I|66|US|29|to2=yes|dir2=south|name2=[[Whitehurst Freeway]]|location1=[[Northern Virginia|Virginia]]}}
|notes=Western terminus
}}
{{DCint
|mile=0.1
|type=incomplete
|road=[[Virginia Avenue]]&nbsp;/ 23rd Street
|notes=Eastbound exit only
}}
{{jctbridge
|mile=0.1
|mile2=0.3
|bridge=Tunnel underneath [[Virginia Avenue]]
}}
{{DCint
|mile=0.3
|road=20th Street&nbsp;/ E Street east
|notes=Eastern terminus; [[at-grade intersection]]
}}
{{jctbtm|keys=incomplete}}